update flake.nix: clean source without removing necessary files

update invoice serialization test

update .gitignore

Minor spacing improvement to invoice

Ask for addr3 only if addr2 is present

Edit invoice if it already exists

Add conditions field to invoice

Update flake.*

cargo update

Add address line 3

Update TODOs

Fix payment method latex rendering (was being escaped)

Add show_tex CLI flag for invoices and receipts

impl Display for PaymentMethod

Add Me to config. Load config once and pass everywhere